Glutathione and ascorbic acid in tissues of normal and tumour-bearing albino rats

A POWERFUL reducing substance giving the indophenol reaction for ascorbic acid was shown by Birch and Dann [1933] to be present in a wide variety of animal tissues in amount comparable with the glutathione present. It then became apparent that values for tissue glutathione determined by methods depending upon its reducing capacity might include both glutathione and ascorbic acid. In tumour tissue, using a colorimetric nitroprusside method, Boyland [1933] showed that only about one-third of the total iodine value was due to glutathione whilst the remainder could be accounted for by the indophenol titration as ascorbic acid. It should be pointed out however that it is not yet certain that the material in all tissues reacting in this method is actually ascorbic acid.